1. Field of the Invention
The present invention relates to ligation devices and methods, and more particularly to devices and methods for accurately locating and ligating an anatomical vessel.
2. Brief Description of the Related Art
The Doppler effect is currently utilized in many fields. For example, Doppler stethoscopes and Doppler wands are currently utilized to listen to the blood flow within the anatomical structures in patients, especially in mammalian patients. Continuous wave Doppler sound signals are used to identify blood vessels, but do not provide feedback as to the distance of the vessel from the Doppler probe used. Pulsed wave Doppler has been used to identify blood vessels and, in conjunction with two dimensional (2D) imaging systems, identify the distance to a blood vessel and blood flow characteristics. Ultrasound systems with Doppler imaging are also currently used in medical fields, and typically produce gray-scale two-dimensional images. The addition of Doppler processing allows for the evaluation of fluid flow velocities through fluid conduits within the patient, and the relative position of these vessels to other anatomical structures.
Ligation devices have previously been proposed. These prior ligation devices have typically been used in laparascopic procedures, and have typically required that the anatomical feature of interest be dissected or visualized prior to ligation of that feature. Other ligation devices require the penetration of a tissue bundle encapsulating the anatomical vessel in order to perform location and ligation of the vessel.
The tissue of the vaginal wall is very elastic, pliable, and flexible. The vaginal wall can made to assume different shapes without tearing and without significant patient discomfort or pain. Heretofore, this inherent characteristic of these tissues has not been utilized in the area of tissue ligation.
According to a first exemplary embodiment, a method of preparing an anatomical vessel contained within a tissue bundle for ligation, comprises the steps of positioning a cannula adjacent to the tissue bundle, wherein the positioning is non-penetrating, the cannula including a first extendable member, a second extendable member, a Doppler wand, and a distal end, transmitting ultrasound signals toward the vessel through the tissue bundle with the Doppler wand, receiving ultrasound signals reflected by the vessel through the tissue bundle with the Doppler wand, invaginating the tissue bundle with the first extendable member on a first side of the tissue bundle, invaginating the tissue bundle with the second extendable member on a second side of the bundle opposite the first side, and interpenetrating a length of ligation material between the first and second extendable members on a side of the vessel opposite the cannula distal end.
According to a second exemplary embodiment, a ligation device for invaginating a vessel contained within a tissue bundle comprises a means for noninvasively positioning a cannula about the tissue bundle, the cannula including a Doppler wand and a distal end, a means for transmitting ultrasound signals toward the vessel through the tissue bundle with the Doppler wand, a means for receiving ultrasound signals reflected by the vessel through the tissue bundle with the Doppler wand, a first means for invaginating the tissue bundle on a first side of the tissue bundle, a second means for invaginating the tissue bundle on a second side of the bundle opposite the first side, and a means for interpenetrating a length of ligation material between the first and second invaginating means on a side of the vessel opposite the cannula distal end.
Still other objects, features, and attendant advantages of the present invention will become apparent to those skilled in the art from a reading of the following detailed description of embodiments constructed in accordance therewith, taken in conjunction with the accompanying drawings.